What is the dimension of the matrix #[(7),(8),(9)]#? Precalculus Matrix Algebra Identity Matrix 1 Answer Alan P. Dec 16, 2016 #3xx1# Explanation: number of rows by number of columns Answer link Related questions What is an identity matrix? How do I find the additive identity matrix? What is the identity matrix for subtraction? What is the identity matrix of size 4? What does an identity matrix do? What is the identity matrix of a #2xx2# matrix? What is the identity matrix of a #3xx3# matrix? How do I find the identity of a matrix on a graphing calculator? What is a unit matrix? How to determine whether a matrices are in echelon form, reduced echelon form or not in echelon form ? See all questions in Identity Matrix Impact of this question 2231 views around the world You can reuse this answer Creative Commons License